New Study Emphasizes Environmental Factors in Cause of Autism | Autism Key

New Study Emphasizes Environmental Factors in Cause of Autism | Autism Key

A new study is finally shifting the official discussion of the cause of autism from mainly heredity to a combination of genetic and environmental influences.

Researchers examined 192 pairs of identical and fraternal twins whose cases were drawn from California databases. At least one twin in each pair had classic autism and in many cases, the other twin also had classic autism or Asperger’s Syndrome. Since identical twins share 100 percent of their genes and fraternal twins share 50 percent of their genes, comparing autism rates in both types of twins enabled researchers to measure the importance of genes versus shared environment.